Hitch receivers are commonly used for attaching accessories to vehicles. The accessories are bicycle racks, cargo baskets, or various carriers and the like, and they are usually attached to a vehicle at its back end. Typically, a hitch receiver is a tube which is substantially square in cross-section (often with rounded corners) with a protruding ring about the outward-facing edge and attached to the vehicle beneath a rear bumper. The accessory is typically intended to support and hold one or more bicycles, cargo, or other similar articles.
The typical hitch receiver is ideal for supporting the typical accessory because the hitch receiver is located at the back end of the vehicle and is securely attached to the vehicle. For example, the hitch receiver is commonly welded or otherwise secured to a chassis or frame of the vehicle.
Various devices for connecting an accessory to a hitch receiver are known, but such devices suffer from a number of imperfections or weaknesses. Many of these imperfections arise because of the requirements that the connecting device should be easy to insert into the hitch receiver, and easy to attach securely to the hitch receiver after insertion. For example, accessories connected to hitch receivers by known devices tend to wobble relative to the hitch receiver (and the vehicle) as the vehicle travels, even where the connection is relatively secure. If not secured again to the hitch receiver after wobbling starts, the connecting device can gradually become less secure, even to the extent of disconnection. In addition, wobbling movement of the accessory relative to the hitch receiver can lead to the bicycles or other cargo on the accessory being jarred loose, and falling off the accessory. Also, known connecting devices do not provide for relatively fast and simple disconnection of the accessory from the hitch receiver.
Clamps and similar fasteners are often used to minimize movement of the accessory relative to the hitch receiver. However, these known clamps usually operate to secure the accessory to any two of four sides of the hitch receiver, so these clamps permit movement of the accessory relative to the hitch receiver in two directions. Other approaches have been to attempt to secure the hitch bar from the inside of the hitch receiver using a fitted plate and draw bolt or by using a split wedge drawn up inside the hitch receiver by use of a dog-legged bolt. These are both inadequate solutions due to the extra modifications and mechanics involved in fitting the pieces together.
U.S. Pat. No. 7,077,417 to Shoemaker addresses this problem through the use of a wedge-shaped (incurvate, actually) bar inserted into a hitch receiver, the purpose of which is to have the expanding sides of the bar contact the inside of the hitch receiver as the bar was drawn into the hitch receiver via a screw action component. This arrangement presents the possibility of weakening and perhaps even splitting the hitch receiver much the same as a wedge driven into a piece of firewood splits the wood. A failure of this type would render the hitch receiver unusable, necessitating its replacement, or worse, could cause the loss of an accessory (or subsequent towing application) at highway speeds.
A better concept would be to compress the hitch receiver from the outside in, as contrasted to expanding the hitch receiver from the inside out. This yields two significant benefits: a) a reduction in the chance of premature fatigue failure of the hitch receiver, and b) greater lateral stability by gripping the outside of the hitch receiver rather than the inside (for exactly the same reason that more torque can be applied to larger bolt-heads than to smaller ones).
This approach grips the outside of the hitch receiver due to the realization that the exterior dimensions of a hitch receiver are nearly as universal as the interior dimensions, thanks to the relatively standard size of the reinforcing ring attached to the outboard end of the hitch receiver. Historically this ring has been fabricated out of the next largest square tubing size from that of the hitch receiver's main tube. Recently, some manufacturers have employed a method of using a one-piece tube and deforming the outboard end to mimic the reinforcement qualities of a separate reinforcing ring, but even in these cases the exterior dimensions remain fairly consistent.
The present invention satisfies the need for an improved connecting device for connecting an accessory to a hitch receiver that satisfies the ease-of-attachment requirement as well as solving the lateral wobbling, rattling and loosening problems inherent with previously-described solutions. It also satisfies these requirements by using the existing infrastructure inherent in every hitch receiver on the market, namely the securing pin hole and the protruding ring about the outward end of the hitch receiver. Because of the unique design of the flanged collar, the present invention accommodates various sizes of protruding rings and secures the accessory on all four sides of the hitch receiver with great affect and without having to employ modifications to the hitch receiver.